Printer for data processing machines

ABSTRACT

A printer for use in a data processing machine in which selected type characters are imprinted on a record carrier by actuation of power storage units. The printer includes a plurality of type carriers, each of which is associated with a respective printing arm. A power storage unit is provided for each printing arm for producing the power to drive the respective type carrier. The associated power storage unit and printing arm are connected together via a coupling mechanism. Each coupling mechanism includes: a lever pivotally mounted on the printing arm and having one end connected to the power storage unit; an actuating member which is also movably mounted on the printing arm to limit the pivotal movement of the lever until completion of the imprint operation and to release the lever only upon completion of the operation; and an abutment member arranged to limit the movement of the lever at a new position after the lever is released by the actuating member.

United States Patent [191 Thevis May 6,1975

[ PRINTER FOR DATA PROCESSING MACHINES [75] Inventor: Paul Thevis, Oberndorf (Neckar),

Germany [73] Assignee: Olympia Werke AG,

Wilhelmshaven, Germany [22] Filed: Nov. 13, 1973 [21] Appl. No.: 415,448

Primary ExaminerEdgar S. Burr Assistant Examiner-Edward M. Coven Attorney, Agent, or Firm-Spencer & Kaye 5 7 ABSTRACT A printer for use in a data processing machine in which selected type characters are imprinted on a record carrier by actuation of power storage units. The printer includes a plurality of type carriers, each of which is associated with a respective printing arm. A power storage unit is provided for each printing arm for producing the power to drive the respective type carrier. The associated power storage unit and printing arm are connected together via a coupling mechanism. Each coupling mechanism includes: a lever pivotally mounted on the printing arm and having one end connected to the power storage unit; an actuating member which is also movably mounted on the printing arm to limit the pivotal movement of the lever until completion of the imprint operation and to release the lever only upon completion of the operation; and an abutment member arranged to limit the movement of the lever at a new position after the lever is released by the actuating member.

10 Claims, 5 Drawing Figures PATENTEL MAY 61973 SHEET 1 OF 5 PSJ'ENTEB HAY 6 i975 SHEET 2 OF 5 PRINTER FOR DATA PROCESSING MACHINES BACKGROUND OF THE INVENTION The present invention relates to a printer for data processing machines in which. after setting of the type carriers to the type characters to be printed. the imprint is effected by power storage units which engage at printing arms connected to the type carriers.

Printers of the above-described type are operated such that either a plurality of printing hammers arranged on the printing arms are moved with a sufficient force to strike a record carrier disposed in front of the type carriers or the type carriers which themselves are disposed on the printing arms are moved with a suffi cient force to strike a record carrier disposed in front of a printing abutment. After an imprint has been made. the printing arms are then returned to their starting position by a return member. During impact of the type carrier with the record carrier. however, recoil or bounce effect occurs which produces a multiple imprint and thus a smudged end product. The cause of the recoil leading to such double outlines is twofold. being due to the power storage unit effecting the imprint and to the mass of the actuated levers and arms and the related momentum ofthese members once they are actuated.

In order to avoid such poor printing results. various solutions have been proposed. In German Pat. No. l.273.87 l. for example. a device is disclosed for preventing recoil ofthe printing hammers, which are actuated by tension springs deflected by a guide member.

The tension springs in such an arrangement form the power storage unit for generating the needed power for actuating the members. In the operation of this device.

when the printing hammer is in its tension biased position. the tension spring is deflected to such an extent that upon actuation a power component accelerates the printing hammer in the direction toward the impact point. During this movement towards the impact point. the angle of deflection of the tension spring is changed to such an extent that there no longer exists a power component acting in the printing direction. Upon continued movement of the printing hammer along its path. a further change in the angle of deflection of the tension spring finally produces a power component in the opposite direction away from the point of impact. which pulls the printing hammer away from the impact point immediately upon completion of the imprint.

While with such a device the recoil phenomena can be prevented. a significant drawback is presented in that the force of the tension spring exerted to accelerate the printing hammer is reduced before completion of the imprint by the tension spring which now acts in the opposite direction. so that the full striking energy can no longer be utilized for the imprint. The selection of a stronger tension spring also does not solve this problem because this simultaneously increases the force acting in the opposite direction.

SUMMARY OF THE INVENTION An object of the present invention is to provide a printer ofthe above-mentioned type in which the recoil phenomena are prevented without reducing the strength of the imprint force.

In order to accomplish this objective. the printer according to the present invention is provided with a coupling mechanism for coupling the power generated by a power storage unit to a print arm. where this power is only transferred until the imprint is made and is then disconnected.

If a plurality of separate printing arms and corresponding power storage units are provided in the printer. then a corresponding plurality of such coupling mechanisms are provided. On the other hand. however. it is possible to provide a single member with the plurality of type carriers mounted thereon. such as. for example a printing drum with a plurality of type character rings. in which situation only a single printing arm and power storage unit would be necessary. In this later situation. only a single coupling mechanism is accordingly provided.

Each of the coupling mechanisms includes a lever. which is pivotally mounted at a pivot bearing on the printing arm and has one of its ends connected to the power storage unit. An actuating member is also movably disposed on the printing arm and controls the movement of the lever until an imprint has been made. Only upon completion of the imprint does the actuating member release a pivoting movement of the lever. An abutment is also provided against which the lever. after being released by the actuating member. abuts during the imprint within a region which lies between the pivot bearing and the power storage unit.

It is possible in an advantageous manner with such an arrangement to produce imprints with sharp outlines under utilization of the full impact force. The actuating member arrests the pivotally mounted lever so that the printing arm. the pivotally mounted lever and the actuating member form a unit which is accelerated in the printing direction by the power force generated by the power storage unit. Upon impact of the type carrier with the record carrier. the system is suddenly stopped. but the actuating member. due to its inherent kinetic energy. continues to move. This further movement of the actuating member causes the pivotally mounted lever to be released with the abutment member then becoming the fulcrum for the lever in this position. The power storage unit which is still acting in the printing direction pivots the lever about this abutment member so that the printing arm is pulled away from the impact point. With such an operation. the printing force need not overcome any oppositely directed force until the imprint is completed. Thus the full printing energy is available for the imprint process.

BRIEF DESCRIPTION OF THE DRAWINGS FIGS. I and la are elevational views of two positions occurring in the operation of a first embodiment of the coupling mechanism of the printer according to the present invention.

FIGS. 2, 2a and 2b are elevational views of three positions occurring in the operation of a second embodiment of the coupling mechanism of the printer according to the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIGS. I and la. a printing arm 1 of a printer is mounted via longitudinal holes 2 on bolts 3 so as to be displaceable in a longitudinal direction. At the right end of the printing arm, which is shown broken off in the drawing. there may be disposed. for example. a printing hammer. a type wheel. a type segment or a type carrier of some other configuration. A bearing bolt 4 is fastened to the printing arm 1 so as to form a pivot bearing for a two-armed lever 5 which is pivotally mounted thereon. A tension spring 7 is attached in a bore 6 to act as the power storage unit which produces the printing power.

Two bearing bolts 8, 9 are also fastened on the printing arm I and an actuating member 10 is longitudinally displaceably mounted on the bearing bolts 8 and 9 via a set of longitudinal holes 11 and [2. A tension spring M which is disposed in an opening 13 in the actuating member 10 has one of its ends attached to a bore 15 in the actuating member 10 and its other end attached to a bore 16 in the printing arm I. This tension spring 14 causes the actuating member 10 to abut at the frontal face 17 of the two-armed lever 5.

Referring specifically to FIG. I, in the tensioned state of the tension spring 7 serving as the power storage unit, the printing arm I rests with one shoulder I8 at a rearward limit member 19. The two-armed lever 5 is held by a rod 20 in the position shown. A cam plate 24 is arranged to abruptly release a roller 21, which is operatively connected with the rod 20, when the cam plate is rotated about a bearing 24' in the direction of arrow A as the roller 21 follows the outline of the cam plate 24, to the position shown in FIG. Ia. and this actuates the printing process.

The two-armed lever 5 is initially pivoted counterclockwise from the position of FIG. I, by the action of the tension spring 7 until it abuts at a shoulder 22 of the actuating member 10. Then the tension spring 7 pulls the rigid system of lever 5, actuating member I0 and printing arm 1 toward the right into the printing position. At the moment of imprint, the system is suddenly limited by the impact of the printing member on the record carrier and the printing arm I and the lever 5 are thrown back by a natural recoil movement; the actuating member 10, however, continues to move in its original direction due to its mass inertia until elements 1 and I0 arrive at the position shown in FIG. la. This further movement of the actuating member 10 is stopped by a limit member 23; shoulder 22 of actuating member 10, however, has now been moved out of the pivoting range of the two-armed lever 5, thereby allowing continuation of the pivotal movement of the lever 5 into the position shown in FIG. la.

An abutment member formed by rod 20 which has moved from its initial position of FIG. I and has followed cam plate 24 toward the right, is now disposed in a second position, FIG. Ia, directly in front of the perpendicular arm of the two-armed lever 5 at a point between the bearing bolt 4 and the tension spring 7. As the tension spring 7 pulls the connection bore 6 of the two-armed lever 5 further toward the right, lever 5 becomes supported by rod 20. Rod 20 now acts as a fulcrum for the lever 5, which has been released by the actuating member 10. so that the printing arm 1 is retracted as long as the tension spring 7 continues to act in the same direction. The actuating member 10 now comes to abut against lever 5 with its second shoulder 25. The rod 20 is then moved back into its starting position by cam plate 24 and acts as a collecting rod for all of the printing arms contained within the printing mechanism. The rod 20 accordingly moves the system back to a point where printing arm 1 abuts with its shoulder 18 at the rearward limit member 19. The further rearward movement of collecting rod 20 now pivots the two-armed lever 5 into its starting position so that the actuating member 10 can also return to its starting position by action of tension spring 14. The system is then back in the position shown in FIG. 1.

FIGS. 2, 2a and 2b show a second embodiment of the printer mechanism which is provided with a printing arm which is pivotal about an axis 31. An angled portion 32 of the printing arm 30 engages with an arcuate slit 33 in a type carrier 34. This type carrier 34 is pivotally mounted in a guide 36 by use of a bolt and can be moved toward a printing abutment 37 of a record carrier. In this way, each one of the printing type characters 38 can be preset before an imprint is made.

A two-armed lever 39 is pivotally mounted about a bearing bolt 40 on the printing arm 30. A tension spring 42 is attached in a bore 41 at the right end of the twoarmed pivotal lever 39 and acts as the power storage unit for driving the members. The left end of lever 39 cooperates with an actuating member 43, which is also pivotally mounted on the printing arm 30 about a bearing bolt 44. A tension spring 45, which is attached at one of its ends in a bore 46 of the printing arm 30 and at its other end in a bore 47 of the actuating member 43, causes the actuating member 43 to abut the frontal face 48 of the left arm of the lever 39. The printing arm 30 is also guided in slits 49 of a guide metal sheet 50.

In the starting position, lever 39 and rod 53 are in the position shown in FIG. 2a, the lever being held in posi tion by rod 53. After setting the type carrier 34 to the desired printing type character 38, rod 53 is moved into the position shown in FIG. 2. The lever then comes to rest against a shoulder 54 of the actuating member 43, as shown in FIG. 2, under the action of tension spring 42. Now the components including the lever 39, the actuating member 43 and the printing arm 30 form a rigid unit which is pivoted under the influence of the tension spring 42 about an axis 31 until the preselected printing type character forcefully reaches the impact point. The mechanism now has reached the position shown in FIG. 2. While the type carrier 34, the printing arm 30 and the pivotal lever 39 are stopped by the impact, the actuating member 43 due to its inertia, or momentum, continues to pivot about its bearing bolt 44, clockwise from the position of FIG. 2, until the edge 55 of its perforation contacts axis 31, thereby stopping the actuating member.

Since shoulder 54 of the actuating member 43 has now been moved out of the pivoting range of the lever 39, thereby releasing the lever, the lever continues to move in a clockwise direction. The lever 39 comes to rest, with the region of its right arm which is disposed between the bearing bolt 40 and tension spring 42, abutting against the rod 53 so that, as in the first embodiment. a fulcrum is produced. The tension spring which continues to act in the same direction now pivots, by means of lever 39, the printing arm 30 away from the impact point about rod 53.

Bearing bolt 40 thereby is moved back into its initial position, shown in FIG. 2b, and lever 39 becomes positioned in position 56. The movement of printing arm 30 back into its starting position is stopped by its guide arm 57 at abutment 58 of slit 49.

The return of the various members to their initial positions is effected by returning a collecting rod, for example rod 53, to its starting position. FIG. 2a. Lever 39 is pivoted back to its starting position until actuating member 43 is repositioned in its rest position of FIG. 2a due to the action of its tension spring 45.

In accordance with the present invention. it is also possible to use a one-armed lever instead of the twoarmed levers 5, 39, the actuating members 10. 43 need not be held by tension springs 14, 45 but could be returned to their respective starting positions by a common collecting rod and a fixed abutment could be provided at the point where in the illustrated embodiments rod 20, 52 takes over the role of a fulcrum for levers 5, 39.

It will be understood that the above description of the present invention is susceptible to various modifications, changes and adaptations, and the same are intended to be comprehended within the meaning and range of equivalents of the appended claims.

I claim:

1. In a printer for use with a data processing machine. the printer being composed of: a plurality of type carriers each settable to print a respective type character; a printing arm arranged for movement in a direction to cause each type carrier to effect a printing operation; and power storage means operatively associated with said printing arm to provide operating power to drive said printing arm in a manner to produce a printing operation. the improvement comprising coupling means operatively disposed between said printing arm and said power storage means and including: lever means mounted for pivotal movement about a pivot bearing on said printing arm and having one end connected to said power storage means; actuating means movably mounted on said printing arm and arranged for limiting the pivotal movement of said lever means until completion of a printing operation and for releasing said lever means upon completion of such operation; and an abutment member arranged for further limiting the movement of said lever means during such printing operation. said abutment member lying in an area between the pivot bearing and the connection of said lever means to said power storage means.

2. An arrangement as defined in claim 1 wherein said lever means is a two-armed lever, with one arm being arranged to cooperate with said actuating means and the other arm with said power storage means.

3. An arrangement as defined in claim I wherein said actuating means is mounted so as to be displaceable in the direction of movement of said printing arm to efi'ect a printing operation; and said coupling means further comprises spring means connected to said actuating means for biasing said actuating means in a direction away from such direction of movement.

4. An arrangement as defined in claim 3 further comprising limiting means for limiting movement of said actuating means so that the movement of said actuating means is only sufficient to release said lever means.

5. An arrangement as defined in claim 1 wherein said actuating means is pivotally mounted on said printing arm; and said coupling means further comprises spring means connected to said actuating means for biasing said actuating means in a direction away from the direction of movement of said printing arm to effect a printing operation.

6. An arrangement as defined in claim 5 further comprising limiting means for limiting movement of said actuating means so that the movement of said actuating means is only sufficient to release said lever means.

7. An arrangement as defined in claim 1 wherein said abutment member is a movable collecting rod against which said printing arm. via said lever means, rests; said collecting rod being movable into a position forming a rest member against which said lever means comes to rest upon completion of a printing operation.

8. An arrangement as defined in claim I wherein said power storage means is a tension spring.

9. An arrangement as defined in claim I wherein said printing arm is mounted for movement in translation to cause each type carrier to effect a printing operation.

10. An arrangement as defined in claim I wherein said printing arm is mounted to undergo pivotal movement.

a a a a: 

1. In a printer for use with a data processing machine, the printer being composed of: a plurality of type carriers each settable to print a respective type character; a printing arm arranged for movement in a direction to cause each type carrier to effect a printing operation; and power storage means operatively associated with said printing arm to provide operating power to drive said printing arm in a manner to produce a printing operation, the improvement comprising coupling means operatively disposed between said printing arm and said power storage means and including: lever means mounted for pivotal movement about a pivot bearing on said printing arm and having one end connected to said power storage means; actuating means movably mounted on said printing arm and arranged for limiting the pivotal movement of said lever means until completion of a printing operation and for releasing said lever means upon completion of such operation; and an abutment member arranged for further limiting the movement of said lever means during such printing operation, said abutment member lying in an area between the pivot bearing and the connection of said lever means to said power storage means.
 2. An arrangement as defined in claim 1 wherein said lever means is a two-armed lever, with one arm being arranged to cooperate with said actuating means and the other arm with said power storage means.
 3. An arrangement as defined in claim 1 wherein said actuating means is mounted so as to be displaceable in the direction of movement of said printing arm to effect a printing operation; and said coupling means further comprises spring means connected to said actuating means for biasing said actuating means in a direction away from such direction of movement.
 4. An arrangement as defined in claim 3 further comprising limiting means for limiting movement of said actuating means so that the movement of said actuating means is only sufficient to release said lever means.
 5. An arrangement as defined in claim 1 wherein said actuating means is pivotally mounted on said printing arm; and said coupling means further comprises spring means connected to said actuating means for biasing said actuating means in a direction away from the direction of movement of said printing arm to effect a printing operation.
 6. An arrangement as defined in claim 5 further comprising limiting means for limiting movement of said actuating means so that the movement of said actuating means is only sufficient to release said lever means.
 7. An arrangement as defined in claim 1 wherein said abutment member is a movable collecting rod against which said printing arm, via said lever means, rests; said collecting rod being movable into a position forming a rest member against which said lever means comes to rest upon completion of a printing operation.
 8. An arrangement as defined in claim 1 wherein said power storage means is a tension spring.
 9. An arrangement as defined in claim 1 wherein said printing arm is mounted for movement in translation to cause each type carrier to effect a printing operation.
 10. An arrangement as defined in claim 1 wherein said printing arm is mounted to undergo pivotal movement. 